tree: https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git pg_table/v0.0 head: fd150c5a9ef6e3e43818825c69a46de2b427dedf commit: da7c45f8a8af997141e829ae8a9b776b7cb50bf9 [13/18] mm: move cpu_bitmask from mm_struct to pg_table config: arm-randconfig-a001-20200202 (attached as .config) compiler: arm-linux-gnueabi-gcc (GCC) 7.5.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross git checkout da7c45f8a8af997141e829ae8a9b776b7cb50bf9 # save the attached .config to linux build tree GCC_VERSION=7.5.0 make.cross ARCH=arm If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): mm/init-mm.c:37:3: error: implicit declaration of function 'INIT_PT_CONTEXT'; did you mean 'INIT_MM_CONTEXT'? [-Werror=implicit-function-declaration] INIT_PT_CONTEXT(init_mm.pgt) ^~~~~~~~~~~~~~~ INIT_MM_CONTEXT mm/init-mm.c:37:3: error: positional initialization of field in 'struct' declared with 'designated_init' attribute [-Werror=designated-init] mm/init-mm.c:37:3: note: (near initialization for 'init_mm.pgt.<anonymous>') mm/init-mm.c:37:3: note: (near initialization for 'init_mm.pgt.cpu_bitmap[0]') cc1: some warnings being treated as errors vim +37 mm/init-mm.c bb1f17b0372de9 Alexey Dobriyan 2009-06-16 18 c1a2f7f0c06454 Rik van Riel 2018-07-16 19 /* c1a2f7f0c06454 Rik van Riel 2018-07-16 20 * For dynamically allocated mm_structs, there is a dynamically sized cpumask c1a2f7f0c06454 Rik van Riel 2018-07-16 21 * at the end of the structure, the size of which depends on the maximum CPU c1a2f7f0c06454 Rik van Riel 2018-07-16 22 * number the system can see. That way we allocate only as much memory for c1a2f7f0c06454 Rik van Riel 2018-07-16 23 * mm_cpumask() as needed for the hundreds, or thousands of processes that c1a2f7f0c06454 Rik van Riel 2018-07-16 24 * a system typically runs. c1a2f7f0c06454 Rik van Riel 2018-07-16 25 * c1a2f7f0c06454 Rik van Riel 2018-07-16 26 * Since there is only one init_mm in the entire system, keep it simple c1a2f7f0c06454 Rik van Riel 2018-07-16 27 * and size this cpu_bitmask to NR_CPUS. c1a2f7f0c06454 Rik van Riel 2018-07-16 28 */ bb1f17b0372de9 Alexey Dobriyan 2009-06-16 29 struct mm_struct init_mm = { bb1f17b0372de9 Alexey Dobriyan 2009-06-16 30 .mm_rb = RB_ROOT, bb1f17b0372de9 Alexey Dobriyan 2009-06-16 31 .mm_users = ATOMIC_INIT(2), bb1f17b0372de9 Alexey Dobriyan 2009-06-16 32 .mm_count = ATOMIC_INIT(1), bb1f17b0372de9 Alexey Dobriyan 2009-06-16 33 .mmap_sem = __RWSEM_INITIALIZER(init_mm.mmap_sem), f91cb6062ff32b Mike Rapoport 2019-08-06 34 .pgt = { f91cb6062ff32b Mike Rapoport 2019-08-06 35 .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.pgt.page_table_lock), e5db6ff88e6ef1 Mike Rapoport 2019-11-18 36 .pgd = swapper_pg_dir, a661e3799be71e Mike Rapoport 2019-11-19 @37 INIT_PT_CONTEXT(init_mm.pgt) :::::: The code at line 37 was first introduced by commit :::::: a661e3799be71e741ee4d31e1386e9f6f0932b38 x86/mm: split pt_context_t out of mm_context_t :::::: TO: Mike Rapoport <rppt(a)linux.ibm.com&gt; :::::: CC: Mike Rapoport <rppt(a)linux.ibm.com&gt; --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation